Fiction heat and temperature change affect the precision of high-temperature self-lubricating rolling bearings at high temperatures by changing the bearing clearance.In order to investigate the influence of bearing material physical properties and matching on bearing clearance at high temperature,based on the theory of heat conduction, a high-temperature self-lubricating roller bearing clearance change calculation model was established.Nano colloidal TiO2/cermet high temperature inner gradient lubrication layer material was used as high temperature rolling bearing roller material,and the effectiveness of the model was verified by the high-temperature rolling bearing clearance measurement experiment.The effects of frictional heat,environmental temperature changes and different material pairs on the working clearance of roller bearings were analyzed.Studies show that the change in the working clearance of a roller bearing increases with the rise of the ambient temperature.Compared with the change in the clearance caused by the change in the ambient temperature, the frictional heat has a smaller effect on the change in the clearance of the bearing.When the lubricating bearing pair is made of bearing steel material for the inner and outer rings, and the rolling elements are made of microporous ceramics, the clearance changes greatly.When the self-lubricating bearing pair is made of ceramic materials for the inner and outer rings and the rolling elements are made of microporous ceramics, the clearance changes smaller.